CalculatedField.DataSource Property

Specifies the data source, associated with the calculated field.

Namespace: DevExpress.XtraReports.UI

Assembly: DevExpress.XtraReports.v22.2.dll

NuGet Package: DevExpress.Reporting.Core

Declaration

C#

public override object DataSource { get; set; }

VB.NET

Public Overrides Property DataSource As Object

Property Value

Type	Description
Object	A Object representing a calculated field’s data source.

Remarks

To allow a calculated field to get access to data fields available in a data source, specify the DataSource and CalculatedField.DataMember properties. Following that, you can refer to these data fields from within the calculated field’s CalculatedField.Expression.

When a calculated field’s DataSource is empty, the field tries to obtain it from its parent (i.e., the XtraReport object to which the calculated field belongs).

To learn more, see Calculated Fields Overview.

Example

This example demonstrates how to create a calculated field at runtime, and bind the field to the report control’s Text property.

C#

using DevExpress.XtraReports.UI;
using DevExpress.XtraReports.Configuration;
// ...
// Create a report.
XtraReport1 report = new XtraReport1();

// Create a calculated field 
// and add it to the report's collection.
CalculatedField calcField = new CalculatedField();
report.CalculatedFields.Add(calcField);

// Specify the calculated field's properties.
calcField.DataSource = report.DataSource;
calcField.DataMember = report.DataMember;
calcField.FieldType = FieldType.Double;
calcField.DisplayName = "Calculated Field";
calcField.Name = "myField";
calcField.Expression = "[UnitPrice] * [UnitsInStock]";

// Bind the label's Text property to the calculated field.
report.FindControl("xrlabel3", true).ExpressionBindings
            .Add(new ExpressionBinding() {
                EventName = "BeforePrint",
                PropertyName = "Text",
                Expression = "FormatString('{0:c2}', [myField])"
            });

VB.NET

Imports DevExpress.XtraReports.UI
Imports DevExpress.XtraReports.Configuration
' ...
' Create a report.
Dim report As New XtraReport1()

' Create a calculated field 
' and add it to the report's collection.
Dim calcField As New CalculatedField()
report.CalculatedFields.Add(calcField)

' Define the calculated field's properties.
calcField.DataSource = report.DataSource
calcField.DataMember = report.DataMember
calcField.FieldType = FieldType.Double
calcField.DisplayName = "Calculated Field"
calcField.Name = "myField"
calcField.Expression = "[UnitPrice] * [UnitsInStock]"

' Bind a label's Text property to the calculated field.
report.FindControl("xrlabel3", True).ExpressionBindings.Add(New ExpressionBinding("BeforePrint", "Text", "FormatString('{0:c2}', [myField])"))